The present invention is directed generally to solderless electrical connections and, more particularly, to novel electrical connector including a contact for forming a crimped, insulation-piercing electrical connection and a method and termination tool used to effect such a connection.
In recent years, increasing numbers of applications have developed in the communications, data processing and transportation industries requiring electrical connectors which provide reliable solderless interconnections with insulated electrical conductors. This demand has perhaps been greatest in the telecommunications industry where miniaturized, high contact density ribbon connectors are used extensively. Connectors of this general type are disclosed in U.S. Pat. Nos. 3,867,005; 3,902,154; and 3,926,498. Because of the great number of individual conductors terminated in these connectors and because of the close spacing between the individual contacts, reliable solder terminations are difficult to achieve, as well as time consuming and costly to maintain and service. For these reasons insulation-piercing contacts have been developed for use in ribbon connectors and have met with wide acceptance when used to terminate insulated conductors having solid wire cores. Unfortunately, due to the demanding standards in the industry requiring almost negligible change in contact resistance, the insulation-piercing type ribbon connectors have proven unacceptable when used with stranded wire core conductors. Experience has shown that tensile forces applied to the conductors, as well as the cold flow of the insulation surrounding the core, causes the individual strands of the wire core to move and reposition within the insulation-piercing contacts, causing changes in contact resistance. Thus, solder termination ribbon connectors are still used with stranded core insulated conductors.
Accordingly, a need exists for a ribbon connector which provides a satisfactory solderless termination to stranded core insulated conductor, and preferably both stranded and solid core conductors. In addition, in order that the connector be commercially practicable, the termination must be performed with the electrical contact premounted within the connector.